[22.19] Correlations of Lithium Abundance with T$_{eff}$ and [Fe/H] on the Spite Plateau

We use a set of ``homogenized'' observational results for some 90
metal-deficient stars in the Galaxy to re-evaluate claims and counter-claims
concerning the existence of correlations between the Li abundances for
metal-poor stars, T$_{eff}$, and stellar metallicity, [Fe/H].
Molaro, Primas, \& Bonafacio (1995, preprint) argue that previously-reported
slopes in the plateau as a function of these two variables (Thorburn 1994,
ApJ 421, 318; Norris, Ryan, \& Stringfellow 1994, ApJ 423, 386) disappear
when a subset of stars with temperatures based on Balmer line profiles is
adopted. Upon closer examination, both of the Molaro et al.
data and
our own newly-expanded data, we find that these correlations persist, but
several points are worth noting: (a) correlations are most apparent when
subgiants are eliminated from the samples, (b) metallicity trends are evident
only when stars of a wide range of metal abundances are included in the
samples, especially the most metal- poor stars, (c) the tests must be
performed in a multiple-regression environment (i.e., not when T$_{eff}$ or
[Fe/H] is considered the only independent variable), and (d) the results
survive when regression methods resistant to the presence of high-leverage
outliers are applied. Our current best estimate of Li abundance as a
function of T$_{eff}$ and [Fe/H] is:

The slopes of this relationship are consistent, within expected errors, with
the results of Thorburn (1994), who considered the existence of a multiple
correlation of A(Li) with T$_{eff}$ and [Fe/H], and with the results of
Norris et al.
(1994) for an inhomogeneous sample which they divided into
subsamples restricted by metallicity. The reported correlations
appear to be real, in contradiction to the claim of Molaro et al.
(1995).